Electrolytic method.



UNTTEE STATES Patented April 11, 1905.

ALEXANDER S. RAMAGE, OF DETIROITI, MICHIGAN.

ELECTROLYTIC METHOD.

SPECIFICATION forming part of Letters Patent No. 787,221, dated April 11, 1905.

Application filed January 31,1905. Serial No. 248,559.

To /I.// who! if may concern:

Be it lillOWlI that I, anuxn'pun S. Rlruaou, a citizen of the United States, residing at Detroit, in the county of \Vayne and State of Michigan. have invented certain new and useful Improvements in Electrolytic Methods, of which the following is a specification.

According to this invention a metallic salt in aqueous solution is electrolyzed in a suitable cell, usually divided into positive and negative compartments. A metallic hydroxid or a metal is produced at the cathode, according to the nature of the electrolyte, while at the anode a secondary product is obtained by the oxidation of a depolarizing compound, preferably an anilin salt. This process has a double advantage, the depolarizer not only yielding a valuable product, but serving to reduce the electromotive force requisite for the electrolysis. As a depolarizing agent I prefer to use the sulfate or hydrochlorid of anilin, which yield by oxidation the compound known as anilin-black.

In producing anilin-black and soluble hydroxids, such as caustic soda, according to my invention I may electrolyze either the sulfate or the chlorid of sodium, preferably in a cell of the mercury-cathode type or of the gravity type. In either case sodium is deposited at the cathode and converted into hydroxid in the usual manner.

In electrolyzing sodium sulfate I prefer to use anodes of lead. The immediate product is $0., which by reaction with water liberates oxygen according to the equation If ferrous sulfate be electrolyzed in presence of anilin sulfate. anilin-black is formed, as above, metallic iron being deposlted at the Similarly if sodium chlorid cathode. In this case it is not essential that the cell be divided into compartments.

In each of the examples above given one of the anode products is an acid sulfuric or hydrochloric. The anode liquor containing this acid in solution and the anilin-black in suspension is Withdrawn from the cell, prefer-- ably continuously, the anilin-black separated by liltration or otherwise, and the acid liquid utilized for the production of additional quantities of the anilin salt.

Anilin-black is now commonly produced by the careful oxidation of anilin salts by means of pot assium chlorate or potassium bichromate in presence of ammonium vanadatc. It has been proposed to produce anilin-black by the electrolytic oxidation of solutions of anilin salts; but this method is less advantageous than that herein described, because no product other than anilin-black is recovered and because when concentrated solutions are used a considerable proportion of the anilin salt is mechanically lost in the separation of the anilin-black.

I claim 1. The herein-described electrolytic method, which consists in electrolyzing an aqueous solution of a metallic salt with an insoluble anode, recovering a cathode product, and oxidizing an anilin compound at the anode.

2. The herein-described electrolytic method, which consists in electrolyzing an aqueous solution of a metallic salt with an insoluble anode, recovering a cathode product, oxidizing an anilin salt at the anode, thereby producing anilin-black, and separating the anilin-black from the anode liquor.

3. The l1ereindescribed electrolytic method, which consists in electrolyzing an aqueous solution ofa metallic salt with an insoluble anode, recovering a cathode product, oxidizing an anilin salt at the anode, thereby producing anilin-black, separating the anilin-black from the anode liquor, and utilizing the anode liquor for the production of additional quantities of the anilin salt.

In testimony whereof I alIix my signature in presence of two witnesses.

ALFXANDER S. RAMAGE.

\Vi tncsses:

Invme \V. DUI-true, F. A. PLATI. 

